3 Fundamentals of press design

Changing dies
to a weight of 3 t provided the press bed and brackets are equipped with
hard roller bars.
Motorized die change carts
Rail-bound carts for die changing are designed to facilitate the
exchange of tools up to around 20 t in weight. The use of two adjacent
tool tables represents a particularly economical solution, as the set of
dies can be prepared for use when one table is located in the parked
position while production is going on. If the press is fitted with protective
grilles and automatic die clamps, automatic die change is possible.
In the home position, the die is unclamped and the protective grilles
open. The push-pull drive system extends, couples automatically to the
die and pulls the die out of the press (Fig. 3.4.2). Once the cart has been
released, traversed and locked back into the push-in position, the new
die can be pushed into the assembly area.
However, in the case of presses with forward-positioned uprights,
this changeover technique becomes considerably more complex. In
this case, a simple push-pull drive is not sufficient to bridge the distance
between the exchange cart and the press bed. Using an additional
mechanical overrun driveand brackets with roller bars at the press, the
push-pull drive system transports the die all the way to the die stops.
The automatic coupling between the drive and the die-set eliminates
the need for intervention by operating staff.
Metal Forming Handbook / Schuler (c) Springer-Verlag Berlin Heidelberg 1998
Fig. 3.4.1
Swivelling brackets
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